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51.
JP Wester R Breumelhof AB Geers OJ Meuwissen 《Canadian Metallurgical Quarterly》1997,141(33):1621-1623
A 20-year-old man was hospitalised because he nearly suffocated when lying on his back. After bronchoscopy which revealed severe external compression of the airways, suddenly respiratory insufficiency developed. Because a malignant lymphoma was suspected chemotherapy was started, using monotherapy with prednisolone as the risk of acute tumour lysis syndrome (ATLS) is high with polychemotherapy of bulky tumours. Nevertheless ATLS developed, for which haemodialysis had to be applied. The tumour, a T-cell lymphoblastic non-Hodgkin lymphoma with high grade malignancy, was treated successfully with cyclophosphamide, doxorubicin, vincristine en prednisone. ATLS is characterized by hyperkalaemia, hyperuricaemia, hyperphosphataemia, hypocalcaemia, lactate acidosis and acute renal failure. It can occur in the course of aggressive cytoreductive therapy in rapidly growing lymphoproliferative malignancies with large tumour size, due to massive tumour cel lysis. Corticosteroid monotherapy is a very rare cause of ATLS. 相似文献
52.
There is evidence that glycans carrying terminal galactose residues are differently expressed in the sarcoplasm of different muscle fiber types. In this study monoclonal antibodies directed against P blood group antigens Pk: Galalpha1-4Galbeta1-4Glcbeta- and P1: Galalpha1-4Galbeta1-4GlcNAcbeta- were used to detect terminal alpha-galactosylated glycoconjugates on muscle proteins. Electrotransfer of proteins, extracted from human masseter and biceps muscles, to nitrocellulose after polyacrylamide gel electrophoresis (PAGE) and incubation with anti-Pk (CD77) consistently showed two bands with apparent molecular weights of 66 kDa and 64 kDa. In fresh frozen muscle sections from some humans there was endothelial reaction with anti-CD77 in capillaries, venules and veins but not in arterioles and arteries. In muscle samples from other humans there was no staining of endothelial cells. Formalin-fixed human muscle displayed a CD77 reaction with highest accumulation of reaction product at the periphery of the fibers. This may be explained by the presence of Pk glycoconjugates on intermediate filaments in muscle fibers. In preparations of cat masseter muscle proteins the antibodies against P1Pk antigens reacted with a 170 kDa and a 55 kDa band while in preparations of cat biceps brachii only a 55 kDa band was reactive. The specificities of the antibodies were investigated by fluorescence-activated cell sorter (FACS), alpha- and beta-galactosidase digestion and inhibitory sugars. This study indicates that glycans carrying Galalpha1-4Galbeta1- epitopes are expressed on myofibrillar associated proteins. 相似文献
53.
OJ Bergmann S Ellermann-Eriksen SC Mogensen J Ellegaard 《Canadian Metallurgical Quarterly》1995,310(6988):1169-1172
OBJECTIVES: To evaluate (a) the prophylactic effect of the antiherpetic drug acyclovir on oral ulcers in patients with acute myeloid leukaemia receiving remission induction chemotherapy and thus (b), indirectly, the role of herpes simplex virus in the aetiology of these ulcers. DESIGN: Randomised, double blind, placebo controlled trial. SUBJECTS: 74 herpes simplex virus seropositive patients aged 18-84. Thirty seven patients received acyclovir (800 mg by mouth daily) and 37 placebo. The patients were examined daily for 28 days. MAIN OUTCOME MEASURES: Occurrence of herpes labialis, intraoral ulcers, and acute necrotising ulcerative gingivitis. RESULTS: The two populations were comparable in age, sex, type of antineoplastic treatment, and history of herpes labialis. Acute oral infections occurred in 25 of the acyclovir treated patients and 36 of the placebo treated patients (relative risk 0.69 (95% confidence interval 0.55 to 0.87)). This difference was due to a reduction in the incidence of herpes labialis (one case versus eight cases; relative risk 0.13 (0.02 to 0.95)), intraoral ulcers excluding the soft palate (one case versus 13 cases; relative risk 0.08 (0.01 to 0.56)), and acute necrotising ulcerative gingivitis (one case versus eight cases; relative risk 0.13 (0.02 to 0.95)). However, ulcers on the soft palate were diagnosed with similar frequency in the two groups. Isolation of herpes simplex virus type 1 in saliva was reduced from 15 cases in the placebo group to one case in the acyclovir group (relative risk 0.07 (0.01 to 0.48)). CONCLUSION: Intraoral ulcers excluding the soft palate are most often due to infection with herpes simplex virus, whereas ulcers on the soft palate have a non-herpetic aetiology. The findings suggest that acute necrotising ulcerative gingivitis may also be due to herpes simplex virus. Prophylaxis with acyclovir should be considered for patients with acute myeloid leukaemia during remission induction therapy. 相似文献
54.
EW Nielsen JT Gran B Straume OJ Mellbye HT Johansen TE Mollnes 《Canadian Metallurgical Quarterly》1996,239(2):119-130
Sinus cavities are often a major obstacle to the placement of dental implants in the posterior maxilla, especially when early tooth loss has occurred. Several grafting procedures aimed at reducing the expanded volume of these pneumatic cavities have been routinely utilized since 1979. Essentially, these techniques have consisted of recreating the necessary viable bone volume at the floor of sinus cavities by placing different bone substitute materials to allow for the insertion of endosseous implant devices. The progress achieved in the refinement of the surgical procedures and the knowledge acquired in the field of patient screening and selection, choice of biomaterials, management of complications, etc., have made sinus graft surgery highly codified and predictable. A comprehensive statistical study by multifactorial procedures was carried out to establish a Burt Contingency Chart. This chart visualizes the frequencies of all the "modality combinations" among the selected "qualitative parameters" and, by a " factorial analysis", the "multiple correlations", so that the "statistical affinities" that may exist among the same variables can be determined. This critical study endeavors to search for and reveal the favorable clinical, biologic and scientific parameters necessary for the success of sinus graft surgery on short-, medium-, and long-term bases (more than nine years). It is a particularly homogenous study, since all the operative procedures have been carried out exclusively by the author under standardized conditions. The wide variety of biomaterials utilized by the author since 1979 shows the development of bone substitute biomaterials as they have been introduced into the market during the past 15 years. The large number of patients treated, the variety of grafting materials, the important success rate obtained, and the long duration of patient follow-up have been instrumental in enabling us to establish scientifically significant results. Autogenous bone and its combinations with calcium- and phosphorus-containing biomaterials remain undoubtedly the best all-purpose biomaterials. The synthetic biomaterials have their own specific indications according to their stable (non-resorbable) or unstable (resorbable) nature and their rates of metabolic "turnover". Differently treated bones from the tissue bank (if not contaminated or immunologically questionable) behave in a fashion not unlike autogenous bone. Root-form implants are by far the best implants in the reconstructed sinus sites, while other implant types (subperiosteal implants, etc.) inserted beneath the reinforced osseous sinus floor, buccal wall, and pyramidal process, also have their indications. 相似文献
55.
Maya Gussmann Kaare Græsbøll Nils Toft Søren S. Nielsen Michael Farre Carsten Kirkeby Tariq Halasa 《Journal of dairy science》2018,101(1):505-517
Societal pressure to limit the use of antibiotics in livestock production systems, including dairy cattle systems, is consistently increasing. To motivate farmers to reduce antibiotic usage, it is important to understand the factors that determine whether a cow will be treated with antibiotics or not. If farmers' usual practices regarding antibiotic treatments are taken into account, they may be motivated to adopt control measures that can facilitate prudent use of antibiotics and are at the same time cost-effective. In this study, we analyzed database recordings of milk yield and somatic cell count from the routine milk recording scheme, clinical registrations of mastitis and PCR results, and cow factors such as days in milk and parity in relation to antibiotic treatments for 518 dairy herds in Denmark. Farm-wise logistic regressions were used to predict antimicrobial treatment based on these factors. The resulting regression coefficients of 422 herds were further analyzed by principal component analysis and clustering to determine the driving predictors for treatment in different groups of farms. The results showed that determinants that were most important for predicting antibiotic treatments vary from one farm to another. Health indicators such as PCR or somatic cell count were most indicative for treatment on some farms, whereas other groups seemed to depend more on production factors (milk yield) or later culling of the cows. This shows that farmers behave differently and differences can be identified in register data. This information can be considered when developing cost-effective herd-specific control measures of mastitis to promote prudent use of antibiotics in Danish dairy cattle farms. 相似文献
56.
We have recently reported that tetrahedral metallocene complexes containing vanadium(IV) (vanadocene) have potent spermicidal activity against human sperm. The spermicidal activity was dependent on vanadium(IV) as the central metal ion within the bis-cyclopentadienyl (Cp2)-metal complex, but the variation of diacido groups and/or replacement with bidentate ligands coordinated to the Cp2-vanadium(IV) moiety also significantly modulated the spermicidal potency. To assess the structure-activity relationship between vanadocenes and other coordination complexes of vanadium(IV), a set of 11 oxovanadium(IV) complexes with different geometrical configurations were synthesized and evaluated for spermicidal activity by computer-assisted sperm analysis. These complexes included mono and bis ancillary ligands, 1,10-phenanthroline (phen): [VO(phen), VO(phen)2, VO(Me2-phen), VO(Me2-phen)2, VO(Cl-phen), and VO(Cl-phen)2]; 2,2'-bipyridyl (bipy): [VO(bipy), VO(bipy)2, VO(Me2-bipy), and VO(Me2-bipy)2], linked via nitrogen atoms; and 5'-bromo-2'-hydroxyacetophenone (acph): [VO(Br,OH-acph)2], linked via oxygen donor atoms. All 11 oxovanadium(IV) complexes elicited concentration-dependent spermicidal activity at micromolar concentrations (EC50 values: 5.5-118 microM). The bis-phenanthroline complex of oxovanadium(IV), VO(Cl-phen)2, was the most active, and the mono bipyridyl complex, VO(bipy), was the least active; the order of efficacy was VO(Cl-phen)2 > VO(phen)2 > VO(Br,OH-acph)2 > VO(Me2-phen) > VO(bipy)2 > VO(phen) > VO(Cl-phen) > VO(Me2-phen)2 > VO(Me2-bipy)2 > VO(Me2-bipy) > VO(bipy). The neutral complex, VO(Br, OH-acph)2, induced rapid sperm immobilization (T1/2 = 38 sec). The sperm-immobilizing activity of mono- and bis-ligated oxovanadium(IV) complexes was irreversible, since the treated sperm underwent apoptosis, as determined by the flow cytometric quantitation of mitochondrial membrane potential, surface Annexin V binding assay, and in situ DNA nick-end labeling of sperm nuclei. The percentages of apoptotic sperm quantitated by the flow cytometric assay correlated well with the spermicidal potency of oxovanadium(IV) complexes. These results provide unprecedented evidence that the spermicidal and apoptosis-inducing activities of vanadium(IV) complexes are determined by the oxidation state of vanadium as well as their geometry. Because of its rapid and potent sperm-immobilizing activity, the bromo-hydroxyacetophenone complex, [VO(Br,OH-acph)2], may be useful as a contraceptive agent. 相似文献
57.
A mathematical model is developed to describe the flow and mixing of blood and optical fluid used in liquid-guided light for laser angioplasty. The model is based on a two-fluid formulation in which separate transport equations are solved for the blood and the optical fluid. Empirical relations, established in prior work, are used to represent interfluid transport of momentum. Both steady and phasic inflow conditions are considered. Parametric calculations are performed showing effect of relative flow rates of blood and optical fluid, on the mixing phenomena. The relative velocity considered (based on average blood velocity) ranged from 0.08 to 0.28 m/sec. No allowance has been made for ablation of the plaque. The predicted results include spatial distribution of the velocity field and the existence probabilities (volume fractions) that provide a measure of the extent of mixing between the fluids. It is found that the degree of mixing is adversely affected by the relative inflow velocity between blood and optical fluid and the pulsatility of blood inflow. Deep penetration of the optical fluid is predicted at high relative velocity and at the end of diastolic and early systolic stages of the cardiac cycle. 相似文献
58.
The determinants of psychiatric hospitalization, especially nonspecific issues, have been studied extensively. The methodological problem of correlational non-cross-validated findings are seen as contributing to our uncertainties about the critical issues involved in the decision to admit. A cross-validated multiple regression analysis of determinants of hospitalization in an inner-city municipal hospital revealed two determinants of hospitalization: severity of schizophrenic symptoms and active suicidal and/or homicidal ideation. They accounted for one third of the variance without shrinkage. Quasi-experimental designs may be the most efficient means of studying the remaining unexplained variance. 相似文献
59.
Blood samples were obtained from 30 coyotes (Canis latrans) captured in northern Wisconsin in conjunction with radio-telemetry studies. Samples were assayed for seven hematologic values, seven serum chemistries, serum albumin, globulin and total protein. Results are given with respect to sex and age and are compared with available data for captive wild and pen-raised coyotes. Leukocyte counts were greater for males than females and packed cell volumes were greater for adults than young, possibly due to differential response to capture and handling stress. Hemoglobin concentrations and calcium levels suggest differences in nutrition between pen-raised and wild coyotes. Sex and age differences in serum calcium for wild coyotes probably reflect nutritional differences between groups examined. Juvenile coyote serum alkaline phosphatase levels declined curvilinearly with age for coyotes less than one year old, suggesting a possible technique for separating juveniles and yearlings captured in autumn that are released for research purposes. Elevated glucose levels and leukocyte counts in wild coyotes may reflect greater handling stress than for pen-raised and captive coyotes. No significant sex or age effects were found for levels of serum urea nitrogen, total protein, cholesterol, and total bilirubin. 相似文献
60.